I know the pain you are experiencing. I had terrible ear infections as a child and still occasionally now. There is a prescription pain relieving ear drop that your doctor can prescribe. (When I was a child, my mother and grandmother used to warm olive oil and drop in my ear and hold it there with a cotton ball.) Once you get the fluid to drain, the pain will ease. Getting the fluid to drain has been well addressed in other postings. You could also place a warm compress on that ear to help alieviate the pain, too.
(The antibiotic was most likely in case of secondary infection -- your ears, if they don't drain soon!)
Best wishes for a speedy recovery,
R. F.